Farmer's Almanac - How Accurate?

A few weeks ago there was a little bit on the local news about predictions for the weather this winter, and one thing that was said was that the Farmer's Almanac is correct about 80% of the time (I don't have a link off hand to support this, but can dig one up if needed).

So I decided to see how accurate the Farmers Almanac will be this winter, starting with November 1. So far, they have been wrong every day (at least for the mid-Atlantic region).

I am wondering if the Farmer's Almanac really is accurate 80% of the time? Any thoughts?